Mapping the motion of molecules: NIH awards ASU biophysics professor more than $2.5M

December 20, 2019

Arizona State University Professor Steve Pressé was recently awarded more than $2.5 million from the National Institutes of Health as principal investigator for two independent awards. 

Pressé is an associate professor in both the Department of Physics and the School of Molecular Sciences and a member of the Center for Biological Physics initiative, which seeks to apply a computational physics approach to understanding biological phenomena.  Steve Pressé. Download Full Image

These grants will support two independent projects developing methods to extract information on processes occurring deep within living cells. The ability to directly monitor the movement of biomolecules, their assembly into larger clusters, as well as their disassembly within cells, would shed immediate insight into the rules of life.

Adding a little light

There are millions of biomolecules within living cells and trillions of cells within a complex living organism. However, despite how small or insignificant they may seem, it is individual biomolecules, moving and interacting within the cells that contain them, that play the role of primary actors dictating how life unfolds. The catch? They are difficult, not to say impossible, to see in their native environment. 

What’s more, gleaning useful information from the complicated data gathered when monitoring them is far from obvious. Sometimes the fundamental logic of missile tracking technology is the most help in tracking biomolecules. 

Yet missiles and biomolecules present very different scientific problems. 

To begin with, unlike missiles, molecules themselves cannot be directly imaged. Each of the millions of molecules in a cell is nearly identical to another, and special care is needed to track the movement of even just a few. By attaching a light-emitting molecule and examining the ratio of signals to background noise in each pixel of the camera, the positions can be deduced. However, when the biomolecules cross paths, the physics of light as it is emitted makes it difficult to distinguish one from the other. 

The goal of Pressé’s first project is to develop the mathematics needed to deduce the paths of many molecules even as they interact and crisscross the cellular environment. 

A smaller focus 

While the first NIH grant is concentrated on gathering detailed information to deduce entire tracks of biomolecules, it relies on gathering a lot of light — the data from the light-emitting molecules attached to the biomolecular tracks. Gathering a lot of light takes time. 

However, biomolecular events can occasionally happen very quickly. Therefore, new tools are needed to see these. 

Pressé’s second project aims to find new ways to observe and capture data on these processes. If we could learn information from just one light particle, just one pixel on a camera, very quickly, this would tremendously improve the time resolution of data imaging. However, it would also make the new data more difficult to interpret. 

Making sense of it all 

A common thread — and a common challenge — in both projects is data processing and the limited ability of our current mathematics to make sense of the complex data at the molecular scale. Interpreting the data is a delicate process, and at times, even more crucial to the success of the projects than the observation methods themselves. 

Fortunately, the computational capabilities of today’s technology have greatly improved. 

“We can now store large quantities of data today, analyze them and get answers to what biomolecules are doing inside cells if we have the right analysis tools,” Pressé said. “This, in turn, will allow us to not only be descriptive about life’s processes but quantitative as well.” 

More to come

If we had a microscope that could peer into biological samples and reveal each minute happening in exquisite detail — the replication of DNA and how that information is transmitted and processed by the rest of the cell — we would have such a clear understanding of life. No disease would remain a mystery.  

Unfortunately, cells make it very difficult to view and address these answers. Instead, we rely on a combination of imperfect measurements and rudimentary, but improving mathematics, to begin to unravel life’s mysteries.

New methods of observation and computational data analysis from research like Pressé’s will open the doors to more revelations moving forward, and improve our understanding of life and the world around us, one step at a time. 

Dominique Perkins

Events and Communications Coordinator, Department of Physics


Climate and governance: Geography PhD candidate represents ASU at UN convention

December 20, 2019

Peter Crank, an Arizona State University geography PhD candidate and climatologist, found his seat in a packed convention hall in Madrid, opened his laptop and listened with intent as nearly 400 United Nation delegates from around the world negotiated policy to address global climate change.

The science underpinnings discussed were already familiar to Crank, so he instead focused on how it was being framed and communicated for decision-making by international leaders. Peter Crank ASU Peter Crank, PhD in geography candidate, at the United Nations Framework Convention on Climate Change. Photo by Peter Crank Download Full Image

“Knowing the policy outcomes that could come from the general climate science work that I do affects how I frame problems,” Crank said. “It affects how I design my research and how I communicate my results to people. I want to be able to tie my research with the long-term goal of potentially being able to influence U.N. decisions.”

Earlier this month, Crank represented ASU's School of Geographical Sciences and Urban Planning as an observing delegate at the United Nations Framework Convention on Climate Change, known as COP25.

The annual conference is the gathering of the nearly 200 countries that make up the U.N. to discuss international action on climate change. It is from this conference that landmark international treaties such as the 1998 Kyoto Protocol and the 2016 Paris Agreement were produced.

Crank, along with a delegation of eight other ASU students, was chosen to represent the university based on his articulation of how attending the convention would help deepen his work and contribute to the larger ASU community.

COP Hall

United Nations Framework Convention on Climate Change, COP25. Photo by Peter Crank

Policy implications of climate science

Crank’s research at the School of Geographical Sciences and Urban Planning focuses on extreme heat in cities and its impact on health. He specifically is exploring how built environments influence our experience of thermal comfort and the mechanisms by which local governments and other stakeholders can help reduce health risks for residents.

Crank was nominated to attend the convention by David Sailor, director of the Urban Climate Research Center.

“When I heard about the opportunity to nominate students to be part of the ASU observer delegation to COP25, I immediately thought of Peter,” said Sailor, who is also a professor in the School of Geographical Sciences and Urban Planning. “Aside from his genuine interest in and expertise related to climate science, Peter has a deep interest in the intersection between climate challenges and governance. There are significant connections and parallels between global and local climate mitigation efforts.”

At the convention, Crank participated in the first week of activities with the Subsidiary Body for Scientific Technological Advice, a subcommittee that serves as a key liaison to the policymakers that define the larger conference’s aim and scope. This year COP25’s focus was to finalize changes to Article 6 of the Paris Agreement, the mechanism by which the U.N. tracks and quantifies what countries are doing to reverse climate change.

“Being at COP25 really showed me the interconnected nature of trying to address climate change at the global scale and the challenges that come with it,” Crank said. “It’s helped me to better understand the U.N. as a whole and how I as a climate scientist connect into the larger discussion that is going on.”

While focused on the local level, Crank believes his research may have the ability to create ripples of a larger change.

“While the U.N. is addressing the larger-scale issues of greenhouse gas emissions and human rights violations associated with climate change, it puts me at the grassroots side of climate change,” Crank said. “At the forefront of this is a validation of why my research matters, but it also helps me situate it and be able to point to tangible local efforts that can be done to mitigate the impacts of climate change on our daily lives.”

ASU COP25 Delegates

ASU COP25 student delegates in Madrid, Spain. Photo by Peter Crank 

The future of academic climate leadership

Crank joins a select number of ASU students who have attended the United Nations Framework Convention on Climate Change. ASU has sent a delegation of select students, staff and faculty to attend the convention for a number of years.

“Students like Peter represent the future academic leadership around issues such as climate change,” Sailor said. “The more firsthand experience they can accrue early in their academic careers, the more effective they can be at informing processes such as COP25, and at advocating for change down the road.”

Sailor continued, “Peter was a great choice for the ASU delegation. That said, SGSUP has many students who exhibit a similar depth of knowledge, leadership and professionalism. So, I am hopeful that SGSUP students will continue to be selected to attend future COP meetings.”

Crank is grateful for the experience and plans to share it with his colleagues and the greater community across the School of Geographical Sciences and Urban Planning and ASU.

“Being able to have had this experience is not only beneficial to me but to future students, those here at ASU that choose to go to the U.N. and potentially students of my own. I look forward to being able to share my experience with them to help them better understand the intricacies and challenges associated with global governance around climate change.”

David Rozul

Communications Program Coordinator, School of Geographical Sciences and Urban Planning